Abstract. The general quasidifferential expressions
each
of order with complex coefficients and their formal adjoints
are considered on the interval . It is shown in the cases of one and
two singular end-points when all solutions of the equation
and its adjoint
are in (the limit circle
case) that all well-posed extensions of the minimal operator
have resolvents which are Hilbert-Schmidt
integral operators and consequently have a wholly discrete spectrum. This
implies that all the regularly solvable operators have all the standard
essential spectra to be empty. These results extend those of formally
symmetric expression studied in [1], [15] and those of general
quasidifferential expressions in [10], [11], [13].